docs: def report_and_save_keywords(self,relaxation_kwds,precomputed_kwds):
          """Save relaxation keywords to .txt and .pyc file"""
          report_name = os.path.join(self.backup_dir,'relaxation_keywords.txt')
          pretty_relax_kwds = pprint.pformat(relaxation_kwds,indent=4)
          with open(report_name,'w') as wf:
              wf.write(pretty_relax_kwds)
          wf.close()
  
          origin_name = os.path.join(self.backup_dir,'relaxation_keywords.pyc')
          with open(origin_name,'wb') as ro:
              pickle.dump(relaxation_kwds,ro,protocol=pickle.HIGHEST_PROTOCOL)
          ro.close()
  
          if relaxation_kwds['presave']:
              precomp_kwds_name = os.path.join(self.backup_dir,
                                               'precomputed_keywords.pyc')
              with open(precomp_kwds_name, 'wb') as po:
                  pickle.dump(precomputed_kwds, po,
                              protocol=pickle.HIGHEST_PROTOCOL)
              po.close()